The raw sewage discharged from human bodies is typically discharged into a sewage system by use of a flush toilet or the like and then flows into a river after being temporarily contained in a holding tank and purified therein. However, at events such as festivals, athletic events, fairs, meetings and the like, temporary toilet facilities must be provided for disposal of raw human waste. In case of the collapse of houses due to fire, earthquake, typhoon, a temporary toilet is installed in the fire location, disaster place, etc., for preventing disease from generating.
Employed conventionally are movable temporary toilets, most of which have a tank for temporarily storing the raw sewage therein. However, the temporary toilets have the problem that the raw sewage contained in the tank must be sucked into a vacuum truck for collection and the collected raw sewage must be transferred to a raw sewage disposal purifying facility, which is laborious and time consuming and is unhygienic.
Transportation vehicles, such as buses, trains, vessels, etc., which operate over long distance are provided with a tank exclusively used for storing and holding discharged raw sewage. The raw sewage in this tank is subjected to a deodorizing treatment by chemicals and thereafter is collected by a vacuum truck at a terminal or relaying point.
As mentioned above, the raw sewage in conventional temporary toilets or movable transportation facilities is contained as it is discharged from the human body and is collected thereafter. Accordingly, the storing method, the collection method and the disposal method are not modern and are very unhygienic. Accordingly, if the temporary toilet has been used for a long period of time, the discharged raw sewage remains in the tank, which cause a bad smell. Furthermore, since operators dislike disposing of the raw sewage, it is not preferable in view of modernization of maintenance of the temporary toilet.
In an attempt to ameliorate the above problems, there have been proposed several hygienic disposal methods. In one method, for example, chemicals are introduced into the tank where the raw sewage is contained to thereby prevent the bad smell and to effect sterilization of the sewage. This method, however, cannot be used for a long period of time because the chemicals become diluted and costs are high though it is often employed in transportation vehicles.
In another method, the raw sewage is contained in a bag made of vinyl and the like to prevent the diffusion of the bad smell. This method, however, requires a vinyl bag of large size and involves a high cost for disposal thereof, and it is troublesome to separate the raw sewage from the bag. A large scale disposal facility is also required.
In still another method, the discharged raw sewage is directly dried by use of heat from a burner, etc. Since the primary component of raw sewage is a liquid component, a large amount of heat energy is required to remove the liquid component and it takes a long time to effect one time disposal of the raw sewage.
In view of the drawbacks of the conventional methods of disposing of the raw sewage, the present inventor proposed a disposing apparatus having a casing provided with stirring blades and heat holding bodies therein in which the raw sewage is stirred by the rotation of the stirring blades and heated by heat generated by the heat holding bodies whereby the raw sewage is dried in a short period of time and the liquid component which is the primary component of raw sewage is evaporated as disclosed in Japanese Patent Nos. 63-124150, 2-411577, and U.S. Pat. Nos. 4,999,930, 5,058,213, 5,152,074, 5,230,164, 5,257,466, and U.S. patent application Ser. Nos. 07/809 962 filed Dec. 18, 1991 and 07/985 556, filed Dec. 3, 1992, now U.S. Pat. No. 5,261,126.
According to the proposed disposal methods, the raw sewage is heated, evaporated in a casing and diffused into the ambient atmosphere. Before the liquid component is diffused, the components which cause bad smell are resolved by a catalyst so that the liquid water is diffused into the atmosphere as an odorless vapor. It was preferable to employ such a method in view of environmental hygiene and preservation even if such method is employed in crowed buildings and/or by throngs of people.
It is very hygienic to evaporate and stir the raw sewage contained in the airtight tank and such operations can be carried out systematically, which results in not causing a burden to the operators. In the raw sewage disposal apparatus proposed by the inventor of this application, raw sewage is contained in an airtight container (drying cauldron) and the low portion of the airtight container is heated by a heater, etc. to thereby facilitate the evaporation function. Since the liquid component of the raw sewage is evaporated and the raw sewage is dried in such an airtight container, bad smell is not dispersed outside the apparatus, which contributes to the hygienic disposal of the raw sewage. The bad smell component among the evaporated liquid component is oxidized by being forced to contact a catalyst so that the evaporated liquid component can be discharged to the atmosphere with an odorless state. As evident from this, the proposed apparatus is to provide a hygienic disposal structure different from the conventional privy type temporary toilet.
However, in a mechanism for storing raw sewage in the tank and for drying the raw sewage by a stirring blade and heating balls, there is a problem that a large amount of raw sewage cannot be continuously dried since the amount of raw sewage to be disposed of at one time is restricted. Furthermore, there remains in the drying cauldron fibrous substances, ash, etc. among the discharged raw sewage which cannot be evaporated.
If much dust accumulates in the drying cauldron, there is a problem that the heat transmission deteriorates and the stirring blade does not rotate, which impedes the normal drying process. Accordingly, there is required a cleaning process for removing the dust upon completion of the drying process. In a prior art arrangement, since the drying cauldron is fixed, compressed air is supplied to the drying cauldron by a blower, etc., so that the dust in the drying cauldron is forcibly dispelled. According to this method, it is easy to dispel fine dust but additional apparatus such as the blower is required, which makes the mechanism complex. Furthermore, a large lump of dust cannot be dispelled by the compressed air but remains in the drying cauldron so that a complete cleaning cannot be performed. Accordingly, it is desired to attain a mechanism capable of continuously drying and evaporating the raw sewage and also capable of easily removing the dust remaining in the drying cauldron upon completion of the drying process.
It is thus an object of the invention to provide a raw sewage disposal apparatus comprising an incinerator shielded from the outside, a swing shaft rotatably horizontally supported by the incinerator, a drying cauldron fixed to the swing shaft, an introduction port which is defined on the peripheral surface of the drying cauldron for introducing raw sewage in the drying cauldron, a plurality of spherical stirring balls which are accommodated in the drying cauldron and a burner communicating with the lower portion of the incinerator for jetting flame toward the bottom surface of the drying cauldron.
According to the present invention, the raw sewage collected by the stool is once contained in the raw sewage tank and a given amount of the raw sewage is sucked by the pump and transferred to the drying cauldron. Since the drying cauldron is swingably held by the incinerator and the bottom surface thereof is always heated by flame current from the burner, the liquid component which is primary component of the raw sewage which flows into the drying cauldron is evaporated. In the drying process of the raw sewage, the drying cauldron is swung at an angular interval to the extent where the raw sewage is not scattered and is uniformly heated. At the same time, the stirring balls accommodated inside the cauldron stir and mix the raw sewage to thereby contribute to the increase of the temperature of the raw sewage. The liquid water evaporated from the raw sewage flows into the deodorizing unit together with the flame current of the burner and is involved in and rotated by the jetted air current which swirls at high speed in the deodorizing unit. Accordingly, the component causing the bad smell is oxidized and is changed to an odorless component while it is mixed with the high temperature air current at high speed and it is finally diffused into the atmosphere.
When the drying process is completed in the drying cauldron, the drying cauldron starts to rotate in a given direction to thereby remove the dust which is not evaporated therein. That is, when the drying cauldron starts to rotate, the stirring balls accommodated in the drying cauldron contact and rotate along the inner peripheral surface of the drying cauldron so that the dust stuck to the inner peripheral surface is peeled off by the stirring balls and drops outside the drying cauldron through the introduction port. Accordingly, since the dust accumulates on the lower portion of the incinerator and the inside of the drying cauldron is cleaned, it is standby for the next drying process. With a repetition of the cycle of these processes, a large amount of raw sewage can be successively dried.